Speed

Speed

Speed is what we use to determine how fast an object is traveling. The fastest speed that has been calculated is the speed of light, which is Its value is exactly 299,792,458 meters per second.

About Speed

In kinematics, the speed of an object is the magnitude of its velocity (the rate of change of its position); it is thus a scalar quantity. The average speed of an object in an interval of time is the distance traveled by the object divided by the duration of the interval; the instantaneous speed is the limit of the average speed as the duration of the time interval approaches zero. Like velocity, speed has the dimensions of a length divided by a time; the SI unit of speed is the meter per second, but the most usual unit of speed in everyday usage is the kilometer per hour or, in the USA and the UK, miles per hour. For air and marine travel the knot is commonly used. The fastest possible speed at which energy or information can travel, according to special relativity, is the speed of light in a vacuum c = 299,792,458 meters per second, approximately 1079 million kilometers per hour (671,000,000 mph).